140 DESCRIPTIONS OF MINERALS. 
Malachite.—Green Copper Carbonate. 
Monoclinic. Usual in incrustations, with a smooth tube- 
rose, botryoidal, or stalactitic surface ; structure finely and. 
firmly fibrous. Also earthy. 
Color hght green, streak paler. Usually nearly opaque ; 
crystals translucent.. Lustre of crystals adamantine inclin- 
ing to vitreous; but fibrous incrustations silky on a cross 
fracture. Earthy varieties dull. H.=3:5-4. G.=3°7-4. 
Composition. Cu,O,C+H, O=Carbon dioxide (or car- 
bonic acid) 19:9, copper oxide 71:9, water 8:°2=100. Dis- 
solves with effervescence in nitric acid. 
B.B. decrepitates and blackens, colors the flame green, 
and becomes partly a black scoria. With borax it fuses to a 
deep-green globule, and ultimately affords a bead of copper. 
Diff. Readily distinguished by its copper-green color and 
its associations with copper ores. It resembles a siliceous 
ore of copper, chrysocolla, a common ore in the mines of the 
Mississippi Valley; but it is distinguished by its complete so- 
lution and effervescence in nitric acid. The color also is not 
the bluish green of chrysocolla. 
Obs. Green malachite usually accompanies other ores of 
copper, and forms incrustations, which, when thick, have 
the colors banded and delicate in their shades and blending. 
Perfect crystals are quite rare. The mines of Siberia, at 
Nischne Tagilsk, have afforded great quantities of this ore. 
A mass, partly disclosed, measured at top 9 feet by 18; and 
the portion uncovered contained at least half a million 
pounds of pure malachite. Other noted foreign localities 
are Chessy, in France; Sandlodge, in Shetland; Schwatz 
in the Tyrol; Cornwall; the Island of Cuba; Serro do 
Bembe, west coast of Africa; copper mines of Australia ; 
Chili. 
The copper mine of Cheshire, Conn., has afforded hand- 
some specimens ; also Morgantown, Perkiomen, and Phoenix- 
ville, Penn. ; Schuyler’s Mine, and the New Brunswick 
copper mine, N. J. ; it occurs also in Maryland, between 
Newmarket and Taneytown ; and in the Catoctin Mountains ; 
in the Blue Ridge, Penn., near Nicholson’s Gap ; also in 
ntic district, Utah. 
TiAt Mineral Point, Wisconsin, a bluish silico-carbonate of 
ocpper occurs, which is for the most part chrysocolla, or a 
mixture of this mineral with the carbonate. 
